Many transdermal adhesive patches are known which provide a non-steroidal anti-inflammatory agent via skin absorption, however they have a problem in that the storage stability of non-steroidal anti-inflammatory agents, and in particular non-steroidal anti-inflammatory agents containing a carboxyl group or their salts, was low.
For this purpose, in International Publication No. WO96/08245, an adhesive patch is described wherein a non-steroidal anti-inflammatory agent having a carboxylic acid group in the molecule is blended with a base material comprising a styrene-isoprene-styrene block copolymer and polyisobutylene as a base polymer, L-menthol as a solvent, a rosine ester derivative as a tackifier, liquid paraffin as a plasticizer, and fatty acid metal salt as an esterification inhibitor which prevents esterification of the above non-steroidal anti-inflammatory agent with L-menthol, is proposed. Also, in Japanese Unexamined Patent Publication No. 2002-226366, an adhesive patch wherein a metal oxide is blended as an esterification inhibitor which prevents esterification of a non-steroidal anti-inflammatory agent having a carboxylic acid group in the molecule with L-menthol, is proposed. Further, in Japanese Unexamined Patent Publication No. 2002-193793, it is proposed to stabilize a non-steroidal anti-inflammatory agent having a carboxylic acid group in the molecule by dissolving it in a glycerin and a glycol having 3-30 carbon atoms.